Methods, systems, and devices for the treatment of stenosis

ABSTRACT

Catheter system, devices and methods for diagnosing and treating lateral stenosis causing back pain and or leg pain. The devices comprise a tubular part for insertion into a working cannula to self-position itself safely within the foramen, and minimize the risk of displacement medially or laterally, to prevent nerve or dura injury. An expandable membrane is configured to maintain the catheter device within the foramen. Expansion of this membrane would decompress the nerve within the foramen by opening the foraminal canal as the membrane expands.

RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application,Ser. No. 61/880,372 filed on Sep. 20, 2013.

FIELD OF INVENTION

The present invention relates to devices and apparatus for the treatmentof stenosis, and particularly the use of catheter devices in combinationwith an expandable device for the treatment of stenosis.

BACKGROUND OF THE INVENTION

Disc herniation and degenerative disorders of the lumbar spine areprevalent, deteriorate the quality of life, and are a major health careconcern of the general population.

Lumbar spinal stenosis is defined as the narrowing of the spinal canalin the lumbar region. This is as a consequence of several pathologicconditions, the most common of which is chronic degenerativespondylosis. Other common causes of stenosis include disc herniation,facet hypertrophy, or congenital causes. Absolute stenosis has beendefined as a decrease in the midsagittal lumbar canal diameter of lessthan 10 mm on MRI.

Although there are different ways of describing stenosis, generally thestenosis of the spinal canal can occur centrally or laterally. Patientsoften present with a combination of symptoms from both central andlateral stenosis.

Lateral stenosis can be further classified into three distinct zones:the lateral recess, foraminal zone, and extraforaminal zone.

Lateral recess stenosis is caused by overgrowth of the superiorarticular facet, and ligamentum or capsular redundancy or hypertrophy.Foraminal stenosis may be due to a foraminal disk protrusion, posteriorosteophyte formation, ligamentum or capsular hypertrophy, or loss ofvertical height from degenerative collapse of the disk. Theextraforaminal zone, which is defined as the area lateral to theintervertebral foramen, is most often affected by far-lateral disk andosteophyte pathology.

Spinal nerves (also referred to as “nerve roots”) originate from thespinal cord, remain within the central portion of the spinal canal, andthen exit through the foramen or neuroforamen. The neuroforamenprimarily contains the nerve root exiting from each correspondingintervertebral level. It also contains the dorsal root ganglion (DRG), astructure that contains the cell bodies of the afferent sensory neurons.DRG has a variety of sensory receptors that are activated by mechanical,thermal, chemical, and noxious stimuli. If DRG is impinged within theforamen, in lateral stenosis cases, it can be quite painful, and it canbecome a major source of pain generation.

Spinal stenosis is treated conservatively initially with therapymodalities and medications. Epidural injections with local anestheticsand steroids may be used next. However, these injections may relievepain for a limited period of time only. More importantly, injectionstypically do not influence or improve the functional outcome of patientcondition. The majority of patients report little substantialimprovement in symptoms with repeated treatment.

Decompression surgery is considered only after conservative treatmentshave failed. Currently, there are 2 surgical approaches to decompressthe lateral portion of the canal: medial (or “inside-out”), and lateral(or “outside-in”, or “transforaminal”). Each has its advantages anddisadvantages. The advantage of the medial approach includes surgeonfamiliarity through a laminotomy. The disadvantage of medial approach issignificant bone resection required to get to the foramen, which islocated more laterally, and possible dural tear. This excess boneresection may lead to an iatrogenic instability of the spinal segment ifit is extensive. Also, trying to reach under the facet to decompress theforaminal zone can result in possible injury to the nerve root injurydue to the deep and lateral position of the nerve root within theforamen. The advantage of transforaminal approach includes less or nobone resection, less risk of dural tear, faster recovery due to lessmuscle dissection, less risk of possible epidural scar formation. Thedisadvantages of transforaminal approach include technically demandingapproach, and difficulty in visualizing the content of foramen from thelateral side.

Balloon dilation is currently used in various parts of the bodyincluding esophagus, urethra, coronary arteries, and peripheralarteries. Additionally, balloons have been used to create a void withinvertebral body to restore the height of fractured vertebrae and allowfor filling of the void with cement or bone graft to stabilize avertebral fracture, commonly referred to as Kyphoplasty.

Balloons have also been used to aid in separating tissues or vitalstructures away from a targeted area to be addressed surgically invarious parts of the body, including abdominal surgery.

However, the prior art devices or techniques have not addressed theperforming a less invasive open or percutaneous decompression of thelateral stenosis through the use of balloons.

The use of balloons in the neuroforamen has been discussed in the priorart, but has not addressed the main problem of having adequate controlof the balloon device and the method to specifically localize and targeta specific point within the neuroforamen.

SUMMARY OF THE INVENTION

The present invention is directed towards the use of systems and devicesthat employ catheter devices in combination with expandable structures,e.g. balloons, to treat stenosis. The balloons are utilized to performforaminal decompression, which allows for non-surgical or less invasivesurgical treatment of lateral spinal stenosis by modifying theunderlying pathophysiology.

In one embodiment of the present invention, the expandable structure ofthe present invention is positioned within the foramen of the spine,with the structure used for decompression of spinal stenosis. Thepresent invention may be used for decompression of lateral spinestenosis. For example, the present invention may be used fordecompression in the lateral recess zone, the foraminal zone, or the farlateral (or extraforaminal zone of the spinal canal.

The methods of the present invention include using the systems andmethods used for treating stenosis. The methods can be used for treatingspinal stenosis.

The methods of the present invention include advancing the catheter andinflatable member into the spinal area near where the stenosis occurs.The inflatable member will be advanced, partially inflated, with thesteps repeated until proper positioning of the inflatable member toaddress the stenosis.

The inflatable members used in the present invention can be of varyingsizes, shapes, and materials.

The inflatable members of the present invention provide selectivecontrol of the location of the inflatable member into the spinal area.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an anatomic view of a human spine, showing the differentregions of vertebrae.

FIG. 2 is an anatomic ipsilateral view of the lower back region of thespine, showing the lumbar vertebrae L2 to L5, the sacral vertebrae S1 toS5, and the coccygeal vertebrae.

FIG. 3 is an anatomic posterior view of the lower back region of thespine, showing the lumbar vertebrae L2 to L5.

FIG. 4 is an anatomic distal view of the view of the spine shown in FIG.3.

FIG. 5A is an anatomic superior view of a vertebral body, taken alongline 5A-5A of FIG. 3, depicting the central canal, foraminal zone, andthe extraforaminal zone of the vertebral body.

FIG. 5B is an anatomic superior view of a vertebral body, taken alongline 5A-5A of FIG. 3, but showing spinal stenosis affecting the region.

FIG. 6A is a partially cut-away view of the spinal region as shown inFIG. 3.

FIG. 6B is a partially cut-away view of the spinal region as shown inFIG. 3, but showing spinal stenosis in the region.

FIG. 7A is a partial view of a delivery device 10 of the presentinvention being used in the present invention, with a generallyspherical inflatable member being used within the delivery device.

FIG. 7B is a partial view of a delivery device as shown in FIG. 7A, withthe exception that the inflatable member has a generally barbell shape.

FIG. 8 is partial cut-away perspective view of a delivery device of thepresent invention, with the inflatable member being inflated and a guidewire within the inflatable member.

FIG. 9 is a partially cut-away view of the delivery system of thepresent invention, demonstrating a radiopaque marker on the inflatablemember.

FIG. 10 is a partially cut-away view of the delivery system of thepresent invention, demonstrating an echogenic marker on the inflatablemember in combination with an ultrasound imaging machine.

FIG. 11 depicts a patient lying on an operating table, with thepatient's back exposed, which demonstrates an initial step in performinga procedure according to the present invention.

FIG. 12 depicts an incision in the area depicted in FIG. 11.

FIG. 13 depicts the area around the incision being resected to allowaccess to the area of the spine where insertion of a delivery systemaccording to the present invention will take place.

FIG. 14 is a partially cut-away view of the spinal region as shown inFIG. 6A showing the first position of the delivery system near thespinal region.

FIG. 15 depicts a further step in advancing the delivery system into thespinal area.

FIG. 16 depicts another further step in advancing the delivery system into the spinal area to be treated, with the inflatable member beingslightly expanded.

FIG. 17 depicts another further step in advancing the delivery systeminto the spinal area to be treated.

FIG. 18 depicts the delivery system being positioned as desired withinthe spinal area.

FIG. 19 depicts the delivery of a medicament or other solution to thetreated area.

FIG. 20 demonstrates the spinal stenosis being treated, with theinflatable member being retained in place.

FIGS. 21-29 demonstrate a similar process as described above, with theexception that the delivery device will enter the spinal area from adifferent position.

FIG. 30 depicts a perspective partially cut-away view of an alternatedelivery device of the present invention.

FIG. 31 depicts the device of FIG. 30 with the inflatable member in aninflated position.

FIGS. 32-39 demonstrate a similar process as the process described inFIGS. 21-29, using a delivery device as shown in FIG. 30.

FIG. 40 demonstrates a process similar to the processes described inFIGS. 21-39, with the delivery system being housed in a portable device.

FIG. 41 demonstrates a further step in the process shown in FIG. 40,wherein a guide wire is inserted into the spinal area.

FIG. 42 demonstrates a further step in the process of FIG. 41, wherein acatheter is inserted into the spinal area.

FIG. 43 demonstrates a further step in the process of FIG. 42, whereinthe guide wire is retracted from the spinal area.

FIG. 44 demonstrates a further step in the process of FIG. 43, whereinan inflatable member is deployed in the spinal area.

FIG. 45 demonstrates the spinal stenosis being treated, with theinflatable member being removed from the spinal area.

FIG. 46 demonstrates an alternate delivery method of the deliverysystem, wherein the inflatable member is delivered alongside of theguide wire.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention, which may be embodiedin other specific structure. While the preferred embodiment has beendescribed, the details may be changed without departing from theinvention. While the present invention pertains to systems, devices, andsurgical techniques applicable at virtually all spinal levels, theinvention is well suited for achieving dynamic stabilization oftransverse processes of adjacent lumbar vertebrae. It should beappreciated, however, the systems, device, and methods so described arenot limited in their application to the spine, and could be employed foruse in treating different types of stenosis throughout the body.

The spine (see FIG. 1) is a complex interconnecting network of nerves,joints, muscles, tendons and ligaments. The spine is made up of smallbones, called vertebrae, which are named according to the region of thebody they occupy. The vertebrae in the head and neck region are calledthe cervical vertebrae (designated C1 to C7). The vertebrae in the neckand upper back region are called the thoracic vertebrae (designated T1to T12). The vertebrae in the lower back region are called the lumbarvertebrae (numbered L1 to L5). The vertebrae in the pelvic region arecalled the sacral vertebrae (numbered S1 to S5).

The vertebrae protect and support the spinal cord. They also bear themajority of the weight put upon the spine. As can be seen in FIG. 4A,vertebrae, like all bones, have an outer shell called cortical bone (thevertebral body) that is hard and strong. The inside is made of a soft,spongy type of bone, called cancellous bone. The bony plates orprocesses of the vertebrae that extend rearward and laterally from thevertebral body provide a bony protection for the spinal cord andemerging nerves. The vertebrae also protect the thecal sac as shown inFIGS. 2 and 3. The thecal sac contains the nerve roots for the spinalcord. The spinal cord ends around L1-L2 vertebrae, with the thecal saccontinuing downwardly from there.

The configuration of the vertebrae differ somewhat, but each (likevertebrae in general) includes a vertebral body (see FIG. 5A), which isthe anterior, massive part of bone that gives strength to the vertebralcolumn and supports body weight. The vertebral canal is posterior to thevertebral body and is formed by the right and left pedicles and lamina.The pedicles are short, stout processes that join the vertebral arch tothe vertebral body. The pedicles project posteriorly to meet two broadflat plates of bone, called the lamina. The arrangement can also beviewed in FIG. 4.

Other processes arise from the vertebral arch. For example, two superiorarticular processes (“SAP”) project upward from vertebral arch andprovide an area for adjacent vertebrae to fit together with one another.Three other processes—the spinous process and two transverseprocesses—project from the vertebral arch and afford attachments forback muscles, forming levers that help the muscles move the vertebrae.

FIG. 2 shows the S1 sacral vertebra and the adjacent fourth and fifthlumbar vertebrae L4 and L5, respectively, in a lateral view (while inanatomic association). The sacral and lumbar vertebrae are in the lowerback, also called the “small of the back.” FIG. 3 shows the fourth andfifth lumbar vertebrae L4 and L5 from a different, more posterior,perspective.

As previously described, between each vertebra is a soft, gel-like“cushion,” called an intervertebral disc (see FIG. 2). These flat, roundcushions act like shock absorbers by helping absorb pressure and keepthe bones from rubbing against each other. The intervertebral disc alsobinds adjacent vertebrae together. The intervertebral discs can bend androtate a bit but do not slide. Along with the invertebral discs, thevertebrae also provide protection for the spinal cord and thecal sac byforming the vertebral foramen (FIG. 5A). The foramen may be depictedwith three zones, the foraminal zone, the central canal, and theextraforaminal zone. Stenosis may occur in any of these zones of theforamen, and it is intended that the methods and systems of the presentinvention would address stenosis in any of these areas.

FIG. 5A shows a vertebra with a normal vertebral foramen. The vertebralforamen provides an open spinal canal for the spinal cord and the thecalsac to reside. FIG. 5B shows a vertebra with abnormal narrowing of thevertebral foramen, e.g. showing spinal stenosis. As previouslyexplained, when spinal stenosis occurs, the spinous process overgrowsinto the vertebral foramen, thereby impinging on the spinal cord and/orthe thecal sac and the related spinal nerves. The impingement into thevertebral foramen causes nerve root compression and spinal stenosis,with resulting pain, and discomfort.

As previously discussed, each vertebra also has two other sets of joints(see FIGS. 2 and 3). For a given vertebra (e.g., L4), one pair of facetjoints faces upward (called the superior articular process, SAP) and theother pair of facet joints faces downward (called the inferior articularprocess, IAP). The inferior and superior processes mate, allowing motion(articulation), and link vertebrae together. Facet joints are positionedat each level to provide the needed limits to motion, especially torotation and to prevent forward slipping (spondylolisthesis) of thatvertebra over the one below.

FIGS. 6A and 6B provide another perspective to demonstrate the anatomyshown and described in FIGS. 5A and 5B. The partially cut-away view inFIG. 6A shows the thecal sac sitting within the vertebral foramen, beingprotected by the vertebral body, as described above. However, as shownin FIG. 6B, an impingement of the thecal sac is shown. The disc ispushing into the thecal sac, while the vertebral facet pushes forwardinto the thecal sac. Such an impingement is often a condition of facethypertrophy, or an enlargement or degenerative change in the facetjoint. These degenerative changes in the spinous process and the spinein general can adversely affect the ability of each spinal segment tobear weight, accommodate movement, and provide support. When one segmentdeteriorates to the point of instability, it can lead to localized painand difficulties.

Facet joint fixation procedures have been used for the treatment of painand the effects of degenerative changes in the lower back. In oneconventional procedure for achieving facet joint fixation, the surgeonworks on the spine from the back (posterior). The surgeon passes screwsfrom the spinous process through the lamina and across the mid-point ofone or more facet joints.

II. Representative System of a Delivery Device Used in Treating Stenosis

The present invention is directed towards a system for treating andaddressing conditions caused by stenosis of the joints and isparticularly useful for treatment of spinal stenosis. The system willprovide relief of the vertebral column and the discs from impinging onthe spinal cord and/or thecal sac located in the vertebral foramen.

As shown in FIG. 8, the system 10 generally comprises a catheter 12 thathouses an expandable member 14, 14′, e.g. a balloon. As will bediscussed in further detail, the catheter will generally be introducedinto the vertebral foramen by way of a working cannula 15. The systemmay also include a guide wire 16 to assist in directing the catheterinto the vertebral foramen. Preferably the guide wire 16 is attached tothe working cannula 14 at the proximal end 18 by a screw fitting 20 orother common arrangement that will allow the guide wire to be attachedor removed as necessary.

FIGS. 7A and 7B demonstrate different shaped expandable members 14, 14′that may be used in the system. In FIG. 7A, a spherical expandablemember 14 is shown, while a dumbbell-shaped expandable member 14′ isshown in FIG. 7B. The dumbbell-shaped expandable member 14′ may bedesigned so that the middle section 22 is less expandable than thedistal 24 and proximal portions 26 (see FIG. 8). In certain situations,as discussed below, such an arrangement will provide for the expandablemember 14′ to act as anchor between the medial and lateral sides of avertebral facet joint. The expandable member 14′ may be made ofdiffering materials that allow the distal 24 and proximal portions 26 toexpand quicker than the central portion 22 of the expandable member 14′.

To assist in proper positioning of the expandable member 14, 14′, amarker 28 may be located on the end or tip of the expandable member. Forexample, a radiopaque marker (demonstrated in FIG. 9) may be used tovisualize the expandable member 14, 14′ position during fluoroscopy.Alternatively, an echogenic marker (demonstrated in FIG. 10) could beused in combination with an ultrasound device for ultrasonic guidance ofthe expandable member 14, 14′.

To assist in the treatment of stenosis, the catheter 12 is also designedso that the pressure within the expandable member 14, 14′ can bemeasured, so that proper positioning of the expandable member 14, 14′when deployed will occur. The volume may also be measure, for examplewith the use of a dyed fluid being injected into the expandable member.

The system is also designed so that various solutions, treatments, andsubstances can be injected into the treated area. For example,anesthetics, steroids, growth factors, stem cell material, or othermedicinal materials, may be injected through the system into the treatedforaminal space.

As will be discussed below, the system 10 is designed so that theexpandable members can be advance into the vertebral foramen to addressthe stenosis and, eventually, removed from the foramen once the stenosishas been addressed.

III. Representative Methods for the Treatment of Stenosis

The present invention includes methods for the treatment of stenosis. Asgenerally discussed above, stenosis is caused by an impingement into aforamen, thereby constricting the thecal sac, nerves, or spinal cordthat may be located within the foramen. The methods generally aredirected towards the use of expandable members 14, 14′ such as balloonsthat are inserted into the foramen. The expandable members are inflatedin a step-like process to treat the impingement.

As demonstrated below, the methods of the present invention can be usedfor the treatment of spinal stenosis. Spinal stenosis may be caused bythe overgrowth of the superior articular facet, ligamentum, capsularredundancy, hypertrophy, or a combination of these. As described below,there are two main ways of addressing the spinal stenosis according tothe present invention: 1) a mid-line approach that would generally beperformed during a laminotomy, or 2) a percutaneous approach.

Furthermore, the methods described below address issues and problems ofthe prior art, namely having adequate control of the inflatable members14, 14′ used in the methods. The described methods are capable of beingdirected to specifically localize and target a specific point within theneuroforamen. As will be discussed, the present invention allows forcontrol of the inflation of the discussed inflatable members 14, 14′,including control of variables such a pressure and volume for theinflatable members, which allows for precise treatment of the stenosis.

As shown in FIG. 11, a patient will be positioned to provide access tothe patient's back, such as for a laminotomy. A cut will be made alongthe length of the spine (FIG. 12), and the area will be resected toprovide access to the spinal area (FIG. 13). The expandable member willthen be inserted into the resected area, posteriorly to anteriorly untila desired placement and position is found so that the expandable member14 can be properly inflated.

FIG. 14 shows an initial positioning of the catheter 12 as it isintroduced posteriorly through the laminotomy site. The tip 30 of thecatheter 12 is positioned at the beginning of the subarticular zone. Thecatheter 12 will be slowly moved forwardly in a posterior to anteriordirection, further into the foramen (FIG. 15), wherein the expandablemember 14 is slowly inflated (FIG. 16). As previously discussed, thepositioning of the expandable member 14 will be monitored by the use ofa marker, such as a fluoroscopic or echogenic marker.

Once the catheter 12 and the expandable member 14 are determined to bein a safe position, the catheter 12 may be further inserted into theforamen, with the expandable member being further inflated (FIGS. 17 and18). The process of insertion and inflation will be repeated until thesurgeon has determined that the expandable member is properlypositioned. Further, if it is determined that the expandable 14 membermay not be properly inflated or positioned after any particular step,the catheter 12 can be retracted and/or the expandable member 14 can bepartially deflated to reposition the catheter 12 and the expandablemember 14. In this manner, the stepped process will do minimal agitationor discomfort to the patient while carrying out the process.

If necessary, a medicinal or therapeutic material such as anesthetics,steroids, growth factors, stem cell material, or other materials, may beinjected through the system into the treated foraminal space, asdemonstrated in FIG. 19. As shown, the materials are injected using thesame catheter 12 as that which delivered the expandable member 14.However, it may be possible that a second catheter dedicated to thedelivery of these materials may also be employed.

Once treatment and process has been carried out, the expandable member14 and the catheter 12 can be removed, as shown in FIG. 20. Theimpingement on the thecal sac and/or the spinal cord has beenremoved/minimized, thereby treating the stenosis.

The process described can also be carried out from different angles andpositions within the vertebral region. For example, FIGS. 21-29 depictanother embodiment of the process of the present invention, wherein thestenosis is approached percutaneously. As shown in FIG. 21, an incisionis made laterally from where the vertebral area where the stenosis islocated. The catheter 12 and the expandable member 14′ will then beinserted laterally to medially, as demonstrated in FIG. 22.

As with the previously described method, the catheter will be positionedin a safe area at the initial steps of the process. In this instance,the catheter 12 will be positioned near the superior articular process,in an area referred to as Kambin's triangle (i.e. the Safe Triangle)(also see FIG. 4).

Once properly positioned, the catheter 12 can be advanced medially, asshown in FIG. 24. If the further position is determined acceptable, theexpandable member 14′ can be slowly inflated (FIG. 25). Monitoring ofthe position of the catheter 12 and expandable member 14′ can be carriedout by the use of a marker, such as a fluoroscopic or echogenic marker28, as previously described.

The steps of insertion and inflation can be repeated (see FIGS. 26 and27) as many times as necessary until the expandable member 14′ isproperly positioned. The process of insertion and inflation will berepeated until the surgeon has determined that the expandable member 14′is properly positioned. And, as previously discussed, if it isdetermined that the expandable member 14′ may not be properly inflatedor positioned after any particular step, the catheter 12 can beretracted and/or the expandable member 14′ can be partially deflated toreposition the catheter 12 and the expandable member 14′. In thismanner, the stepped process will do minimal agitation or discomfort tothe patient while carrying out the process.

If necessary, a medicinal or therapeutic material such as anesthetics,steroids, growth factors, stem cell material, or other materials, may beinjected through the system into the treated foraminal space, asdemonstrated in FIG. 28. As shown, the materials are injected using thesame catheter 12 as that which delivered the expandable member 14′.However, it may be possible that a second catheter dedicated to thedelivery of these materials may also be employed.

Once treatment and process has been carried out, the expandable member14′ and the catheter 12 can be removed, as shown in FIG. 29. Theimpingement on the thecal sac and/or the spinal cord has beenremoved/minimized, thereby treating the stenosis.

As shown in FIGS. 26-28, the expandable member 14′ is of adumbbell-shape, as previously discussed as one possible shape for theexpandable member. The expandable member will act as an anchor betweenthe medial and lateral sides of the facet joint, thereby minimizing therisk of the expandable member 14′ being displaced into the medial canal,thereby potentially avoiding the risk of dural injury, or displacinglaterally, thereby preventing dislodging of the balloon (expandablemember 14′) laterally and out of the foramen.

As appreciated and understood with such procedures as described herein,there are different layers, e.g. skin and fascia (deep thick layerunderneath the skin), that need to be navigated when performing such aprocedure. Likewise, the present devices and procedures are used aroundsensitive nerves and the foramen. The devices and methods of the presentinvention are designed to be used in such differing areas of the body.For example, to penetrate the skin and the fascia, a sharp device may bedesired to penetrate these layers, while a more blunt device may bedesirous when navigating around the nerves and the foramen. The deliverydevice and system 100 shown in FIG. 30 contemplates such considerations.

The delivery device 100 of FIG. 30 generally comprises a catheter 102.The delivery device 100 comprises a pair of stylets 104 and 106 thatwill be used to for navigation of the delivery device through thevarious layers discusses above. The delivery device also houses aninflatable member 108, and preferably a guide wire 110 to assist inproperly positioning the inflatable member in place.

As shown in FIG. 31, the stylets 104 and 106 of the delivery device 100are telescopingly arranged with one another. The interior stylet 106 hasa blunt end 112, which is beneficial when navigating around the foramenand nerves located in the spinal area. The blunt end 112 of the interiorstylet 106 will also minimize any damage, e.g. puncturing, of theinflatable member 108. The inflatable member 108 shown in Figure isdumb-bell shaped, but, as discussed above, a spherical or other shapedballoon may be used, as noted with inflatable members 14, 14′.

The exterior stylet 104 has an angled or sharpened end 114, whichassists in piercing or penetrating the skin and the fascia. For example,the beveled end 114 of the exterior stylet 104 may have an angle(greater than 0°), e.g. 20° or 30°, that will provide the sharpenededge. To protect the inflatable member 108 from being damaged by theexterior stylet 104, the inflatable member 108 is preferably locatedwithin the interior stylet 106, thereby providing a barrier between theexterior stylet 104 and the inflatable member 108.

FIG. 32 demonstrates a step in the insertion of the delivery device intoa patient. The patient will be initially prepped, as shown previously inFIGS. 21 and 22. Once prepped, the catheter 102 will be positioned in asafe area. The catheter 102 will be positioned near the superiorarticular process, in an area referred to as Kambin's triangle (i.e. theSafe Triangle) (also see FIG. 4). The sharpened end 114 of the exteriorstylet 104 will be used to penetrate the skin and the fascia.

Once properly positioned and the exterior stylet 104 has properly andsufficiently pierced and penetrated the skin and the fascia, theinterior stylet 106 will be extended, as shown in FIG. 33, with theexterior stylet 104 being maintained at the initial position shown inFIG. 32. Once properly positioned in an acceptable position, theinflatable member 108 will then be further extended outwardly from theblunt 112 end of the interior stylet 106 (FIG. 34), and the inflationprocess can commence, with the process being monitored, as previouslydescribed. The guide wire 110 will be used in properly navigating theinflatable member into the proper positioning.

As previously described above, the steps of insertion and inflation canbe repeated as many times as necessary (see FIGS. 35 and 36). Theprocess of insertion and inflation will be repeated until the surgeonhas determined that the expandable member 108 is properly positioned.And, as previously discussed, if it is determined that the expandablemember 108 may not be properly inflated or positioned after anyparticular step, the catheter 102 can be retracted and/or the expandablemember 108 can be partially deflated to reposition the catheter 102 andthe expandable member 108. In this manner, the stepped process will dominimal agitation or discomfort to the patient while carrying out theprocess. Once properly positioned, the guide wire 110 is withdrawn fromthe device (FIG. 35). As previously noted with respect to FIG. 8, theguide wire 110 may be removed by unscrewing the guide wire from thedelivery device.

If necessary, a medicinal or therapeutic material such as anesthetics,steroids, growth factors, stem cell material, or other materials, may beinjected through the system into the treated foraminal space, asdemonstrated in FIG. 37. As shown, the materials are injected using thesame catheter 102 as that which delivered the expandable member.However, it may be possible that a second catheter dedicated to thedelivery of these materials may also be employed.

Once treatment and process has been carried out, the expandable member108 and the catheter 102 can be removed, as shown in FIG. 38, with theinflatable member 108 being retracted into the interior stylet 106. Theinterior stylet 106 is then telescoped inside of the exterior stylet104, and the catheter 102 can be removed. The impingement on the thecalsac and/or the spinal cord has been removed/minimized, thereby treatingthe stenosis.

The system and device can delivered in a similar fashion as described inthe methods above, but with the delivery system being positioned withina portable housing 40. The portable housing is preferably designed sothat it can be hand held. As shown in FIG. 40, the portable housing 40allows deployment of a catheter, in the similar fashion as describedabove. The portable housing preferably has a switch or control device 42that assists in delivery of the guide wire 16 and/or the inflatablemember 14′ (see FIG. 43). The control device 42 may comprise furtherdevices so that the individual parts of the system, e.g. the guide wire16 or the inflatable member 14′ could be individually controlled. Thecontrol device can be used to monitor the volume, e.g. mm³, of theinflatable member 14′, so that the inflatable member 14′ will beproperly inflated.

FIG. 40 shows the catheter 12 being properly positioned in the spinalarea, as described above. Once the catheter is positioned, the guidewire 16 can be introduced into the spinal area, as demonstrated in FIG.41. Once the guide wire 16 is positioned, the cannula 15 that willdeliver the inflatable member 14′ is introduced into the spinal area(FIG. 42).

As an alternate step to the processes discussed above, the guide wire 16is then removed from the spinal area (FIG. 43), prior to the deploymentof the inflatable member 14′ (FIG. 44). It is understood, as describedabove, that the inflatable member can be deployed and retracted asnecessary so that the device can be properly positioned to treat thestenosis (see FIG. 45).

It should be understood that either expandable member shape, or othershapes, could be used with either of the processes described. Providedthat an expandable member was inserted and progressed as described, itis understood that the process will be covered by the presentdisclosure. For example, FIG. 46 demonstrates a delivery step that couldbe used in any of the above procedures. The inflatable member 14′ isdelivered over the guide wire 16, but is used with a portable housing40, as shown in FIG. 40.

The foregoing is considered as illustrative only of the principles ofthe invention. Furthermore, since numerous modifications and changeswill readily occur to those skilled in the art, it is not desired tolimit the invention to the exact construction and operation shown anddescribed. While the preferred embodiment has been described, thedetails may be changed without departing from the invention.

We claim:
 1. A method for treating impingement of a nerve of a spinalcanal caused by spinal stenosis within a human body, said spinal canalincluding a vertebral foramen the method comprising: providing acatheter having an expandable member located within the catheter;providing a cannula having a blunt end with at least one stylet having ablunt end located internally of said cannula; introducing the catheterinto the general proximity of the impinged nerve of the spinal canal;introducing the stylet into the general proximity of the impinged nerveof the spinal canal; advancing the expandable member from the catheterinto the spinal canal in a posterior to anterior position; expanding theexpandable member; alleviating the pressure of the nerve impingement ofthe spinal canal with the expanded expandable member; and removing thecatheter and the cannula and stylet from the human body.
 2. The methodaccording to claim 1, wherein the catheter is introduced with a cannula.3. The method of claim 1, wherein the expandable member is removed afteralleviating the pressure of the impinged nerve.
 4. The method of claim1, wherein the step of expanding the expandable member comprisesincreasing and decreasing the volume of the expandable member.
 5. Themethod of claim 1, wherein the impingement is spinal stenosis.
 6. Themethod of claim 5, wherein the catheter is introduced during alaminotomy.
 7. The method of claim 5, wherein the catheter is introducedpercutaneously.
 8. The method of claim 1, further including the step ofdelivering a guide wire to position the expandable member.
 9. The methodof claim 8, wherein the guide wire is delivered through the catheter.10. The method of claim 8, wherein the guide wire is delivered outsideof the catheter.
 11. The method of claim 8, wherein the expandablemember is delivered over the guide wire.
 12. The method of claim 8,wherein the expandable member is delivered separately from the guidewire.
 13. The method of claim 1 wherein the expandable member is in adumbbell shape when expanded.